no sound from integrated rear-facing speakers on HP w2207h

Help! Just got a Pavillion a6712 with a w2207h monitor. I'm connecting with the green ended cables, monitor to back of tower. I have that speaker chosen. It says it's working, I can't hear a thing. No muting on, volume up fine. I am clueless and waiting for the last 1:34 hr. for HP on the phone. Someone must know what I can try now. Please. Also tried reinstalling the driver to no avail.